> It cracked.

> "Kirk Revolution cast magnesium"

Cast magnesium is really weak/brittle compared to forgings and extrusions. Its use was not a great design decision on Kirk's part. I suppose they could have wrapped the casting in carbon fiber or something like that, to give it extra bending strength and spread out loads that might cause fractures, but then it would get expensive.

I had a Merida Magnesium 909 road bike back in the day. They were common in Australia. Was (wrongly) convinced magnesium was going to overtake carbon. Never had any issues in 10 years of ownership and a lot of kms. Welds looked shocking and it was very rigid and unforgiving though.